Weatherby338/378 shooting inconsistent

I have a new 338/378 Weatherby that I have had pillar bedded, Near scope triple mounts with pictanni rail and a Leupold 6.5X20 - 50MM MK-IV Tactical scope with TMR in 2nd focal plane. My loads are RE25 - one grain over max indicated load (106gn) and Barnes 225Gr TTSX loaded at recommended COAL. (with no pressure signs) I have a fat wrench and have checked all torque values from stock - receiver to scope mounts. My barrel is kept clean with WipeOut. I have about 150 rounds down the pipe with Burger 300gr VLD Hy. and 225gr Hornady interbond. My question here is when I shoot the rifle from a steady bench, seated with a rear bag and bipod, I will get the first 3 rounds at .5inch -100 meters measured. Wait about 5 min for barrel cool down and the next two will be 3 or 5 inches at random on the target with the Barnes 225TTSX 225 grain. I do not clean my barrel for the duration of the 5 rounds.
Any clues what is going on here. Could it be that my barrel is getting fouled with shot 4 and 5? Any suggestions as to what may be happening here would be appreciated. Rifles are strange things and no two are alike but this one is mine.

I just got back from the range and my problem was easy too solve. I added one more grain of RE25 and I put five 225gr TTSX into a 1/2 inch group at 100 meters.
Sometimes comming up a little or dropping a little on your powder can make all the difference in the world.

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